Four-dimensional Painlev\'e-type equations associated with ramified linear equations II: Sasano systems

This is a continuation of the paper “Four-dimensional Painlev'e-type equations associated with ramified linear equations I: Matrix Painlev'e systems” (arXiv:1608.03927). In this series of three papers we aim to construct the complete degeneration scheme of four-dimensional Painlev'e-type equations. In the present paper, we construct the degeneration scheme of what we call the Sasano system.